Amine quinone polyurethane polymers for improved performance in advanced particulate media

The magnetic layer used in commercial, high density, metal particle recordi ng media consists of sub-micron sized Fe particles suspended in a polyureth ane polymer binder. New amine-quinone polymers, AQPU15 and AQPU100, have be en developed for improving corrosion resistance of the particles. A fundame ntal study of the nature of the AQ polymer/metal oxide interface and its re lationship to corrosion resistance is reported. Electrochemical impedance s pectroscopy was used to evaluate corrosion behavior of Fe substrates coated with two different thicknesses of each polymer. The extent of corrosion of Fe particles coated with AQ polymers was also measured via the loss in Ms with time of immersion in an acid solution. AQ coated particles showed sign ificant improvement in corrosion resistance. FTIR-RA and XPS data show an i nteraction between AQM14A, a simple model for a portion of the polymer, and metal (Fe, Cu, Al) surfaces which occurs through the pi system of the AQ f unctional group. (C) 1999 Elsevier Science B.V. All rights reserved.